Radiation therapy uses high-energy x-rays to kill cancer cells and abnormal pituitary cells and shrink tumors. Radiation for pituitary tumors these days almost always comes from a radiation source outside the body (external radiation therapy). Radiation therapy may be used if medication/surgery fails to control the tumor. There are several different types of radiation therapy.
- Standard External Beam Radiotherapy uses a radiation source that is nonselective and radiates all cells in the path of the beam; in almost all cases other portions of the brain in the area of the pituitary are in the path of the radiation beam.
- Proton Beam Treatment employs a specific type of radiation in which “protons”, a form of radioactivity, are directed specifically to the pituitary gland. The advantage of this technique is less damage to tissues surrounding the pituitary gland.
- Gamma Knife Irradiation combines standard external beam radiotherapy with a technique that focuses the radiation through many different ports. This treatment tends to do less damage to tissues adjacent to the pituitary gland. Some clinics are using proton beam therapy; laser-guided MR imaged stereotactic intrasellar tumor localization can be used for selected patients with untreated pituitary tumors, incomplete surgical resection, or tumor recurrence.
